AN 757: 1G/2.5G Ethernet Design Examples

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ID 683753
Date 11/12/2018
Public
Document Table of Contents
Document Table of Contents x
AN 757: 1G/2.5G Ethernet Design Examples
AN 757: 1G/2.5G Ethernet Design Examples x
Features Hardware and Software Requirements Functional Description Using the Design Example Simulation Hardware Testing Interface Signals Configuration Registers Document Revision History for AN 757: 1G/2.5G Ethernet Design Examples
Functional Description x
Design Components Reset Scheme Clocking Scheme
Simulation x
Testbench Using the Simulator Test Case—Design Example without the IEEE 1588v2 Feature
Hardware Testing x
Setup Test Procedure
Interface Signals x
Clock and Reset Interface Signals Avalon-MM Interface Signals Avalon-ST Interface Signals PHY Interface Signals IEEE 1588v2 Timestamp Interface Signals Packet Classifier Interface Signals TOD Interface Signals
Configuration Registers x
Transceiver Reconfiguration
AN 757: 1G/2.5G Ethernet Design Examples

IEEE 1588v2 Timestamp Interface Signals

Table 8.   IEEE 1588v2 Timestamp Interface Signals
Signal Direction Width Description
tx_egress_timestamp_96b_valid[] Out 2 When asserted, this signal qualifies the timestamp, tx_egress_timestamp_96b_data[], and the fingerprint, tx_egress_timestamp_96b_fingerprint[], of the TX frame.
tx_egress_timestamp_96b_data[][] Out [2][96] Carries the 96-bit egress timestamp in the following format:
  • Bits 48 to 95: 48-bit seconds field
  • Bits 16 to 47: 32-bit nanoseconds field
  • Bits 0 to 15: 16-bit fractional nanoseconds field
tx_egress_timestamp_96b_fingerprint[][] Out [2][TSTAMP_FP_WIDTH]

Specifies the fingerprint of the TX frame that the 96-bit timestamp is for.

tx_egress_timestamp_64b_valid[] Out 2 When asserted, this signal qualifies the timestamp, tx_egress_timestamp_64b_data[], and the fingerprint, tx_egress_timestamp_64b_fingerprint[], of the TX frame.
tx_egress_timestamp_64b_data[][] Out [2][64] Carries the 64-bit egress timestamp in the following format:
  • Bits 16 to 63: 48-bit nanoseconds field
  • Bits 0 to 15: 16-bit fractional nanoseconds field
tx_egress_timestamp_64b_fingerprint[][] Out [2][TSTAMP_FP_WIDTH]

Specifies the fingerprint of the TX frame that the 64-bit timestamp is for.

rx_ingress_timestamp_96b_valid[] Out 2 When asserted, this signal qualifies the timestamp, rx_ingress_timestamp_96b_data[]. The MAC IP core asserts this signal in the same clock cycle it asserts avalon_st_rx_startofpacket.
rx_ingress_timestamp_96b_data[][] Out [2][96] Carries the 96-bit ingress timestamp in the following format:
  • Bits 48 to 95: 48-bit seconds field
  • Bits 16 to 47: 32-bit nanoseconds field
  • Bits 0 to 15: 16-bit fractional nanoseconds field
rx_ingress_timestamp_64b_valid[] Out 2 When asserted, this signal qualifies the timestamp, rx_ingress_timestamp_64b_data[]. The MAC IP core asserts this signal in the same clock cycle it asserts avalon_st_rx_startofpacket.
rx_ingress_timestamp_64b_data[][] Out [2][64] Carries the 64-bit ingress timestamp in the following format:
  • Bits 16 to 63: 48-bit nanoseconds field
  • Bits 0 to 15: 16-bit fractional nanoseconds field
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